Non-reversing stop.



R. J. MOULTON. NON-REVBRSING STOP.

APPLIOATION TILED DBO.16, 1907. I

Patented June 22, 1909.

W/f/l/TSSES UNITED SATEgPATENT OFFTQE.

RANDOLPH J. MOULTON, OF MINNEAPOLIS, MINNESOTA.

NON-RE VERSING STOP.

To all whom it may concern:

Be it known that I, RANDOLPH J. MoUL- TON, of Minneapolis, Hennepin county, Minnesota, have invented certain new and useful Improvements in Non-Reversing Stops, of which the following is a specification.

The object of my invention is to rovide a non-reversing mechanism which wil permit free revolution of a driven element in one direction but will automatically prevent revolution in the op osite direction.

A further an particular object is to provide a non-reversing mechanism applicable to the shaft of a motor or a counter shaft of an elevator leg drive to prevent backing up of the elevator and consequent clogging of the leg if for any reason the power should be unexpectedly taken off.

The invention consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claim.

In the accompanying drawings, forming part of this specification, Figure 1 is a side view of a non-reversing stop mechanism embodying my invention. Fig. 2 is an end view of the same.

In the drawing, 2 represents a shaft having a driving pulley 3 secured thereon from which the elevator operating in the leg is driven. This elevator leg is of ordinary construction and the manner of arranging the elevating ap aratus therein is the same as is usually emp oyed, and I have not thought it necessary to illustrate the direct application of my invention to this work, although it is designed particularly to prevent the elevating apparatus from running backward and clogging the leg in case there should be at any time, an absence of power to drive the elevator forward.

The shaft 2 has bearings 4 in a frame 5 and a drum divided longitudinally into two sections 6 is loosely journaled on said shaft, and the sections are yieldingly connected by means of bolts 7 and coiled springs 8 thereon. Adjusting nuts 9 permit the tension of these springs to be regulated for the purpose of drawing the drum sections together or allowing them to separate. Ordinarily these nuts will be adjusted so that there will be suf- Specification of Letters Patent.

Application filed December 16, 1907.

Patented June 22, 1909.

Serial No. 406,613.

ficient friction between the shaft and the drum to revolve the latter. A ratchet wheel 10 is secured on the shaft and a dog 11 is pivoted at 12 on said frame and is adapted to engage the teeth of the ratchet and normally lock the ratchet and shaft against backward movement. This dog would permit forward movement of the ratchet and shaft, and to avoid the necessity of keeping the dog in contact with the teeth of the ratchet at all times I provide a cable 13 attached at one end to the dog 11 and passing over a sheave 1 1 and secured at its other end to the drum. When the shaft starts forward the drum will revolve with it and the cable be Wound on the drum and the dog disengaged from the teeth of the ratchet.

hen the dog has been disengaged from the ratchet teeth and the slack of the cable taken up, the drum will slip on its bearing, the shaft continuing to revolve freely to operate the elevating apparatus. As soon, however, as there is absence of power to drive the shaft and it ceases to revolve and the weight of the elevator causes it to start backward, the drum will be turned backward with the shaft until there is sufficient slack in the cable to allow the dog to drop by gravity into engagement with the teeth of the ratchet, whereupon the shaft, the ratchet and the elevating apparatus will be locked against backward movement. The depending arm 15 on the dog 11 tends to swing its op osite end into engagement with the rate iet teeth as soon as the cable is slackened. The dog may be weighted in any other suitable way.

I claim as my invention:

The combination, with a driving element, of a toothed member secured thereon, a dog adapted to engage the teeth of said member and normally prevent backward movement of said driving element, a drum loosely mounted on said driving element, there be ing normally sufficient friction between said driving element and drum to cause the revolution of the drum with said driving element, a cable attached at one end to said drum and at its other end to said dog, and a pulley above the level of said dog and drum and over which said cable passes, the initial forcable and permitting said dog to reengage said toothed member, substantially as de scribed.

In Witness whereof, I have hereunto set my hand this 4th day of December 1907.

RANDOLPH J. MOULTON Witnesses:

J. H. BALDWIN, J. B. BYINGTON. 

